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Old Nov 23, 2012, 06:57 PM
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Originally Posted by LuvEvolution7 View Post
well, the gear aren't really angled to let em all touch at roughly the same time. the gear are angled, so that there's minimal shock transfer to the airframe. if all wheels touch at the same time, shock waves get sent up into the airframe, without being absorbed by the gear itself. if you angle them and allow seperate touchdown events to take place, the impact gets transfered to the gear and rebounds, rather than going up through the legs and into the airframe. pretty simple and ingenious.
Maybe so, but take a look at a 747 landing and the rear tyres on the main gear all touch down close to the same time.
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Old Nov 23, 2012, 08:43 PM
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the 747 gear is designed so that the rear tires of the outer bogeys touch first, then milliseconds later, the rear tires of the inner bogeys touch down, then milliseconds after that, the front tires of the inner and outer bogeys touch at the same time. then of course the nose gear. as I said, it works this way, to minimize shock transfer and rebound to the airframe. ever watched some of the bouncy landing attempts of a 737?................shock transference to the airframe working at its best.
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Old Nov 24, 2012, 04:56 AM
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Originally Posted by LuvEvolution7 View Post
the 747 gear is designed so that the rear tires of the outer bogeys touch first, then milliseconds later, the rear tires of the inner bogeys touch down, then milliseconds after that, the front tires of the inner and outer bogeys touch at the same time. then of course the nose gear. as I said
Well actually that's what I said.
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Old Nov 24, 2012, 06:02 PM
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Originally Posted by LuvEvolution7 View Post
the 747 gear is designed so that the rear tires of the outer bogeys touch first, then milliseconds later, the rear tires of the inner bogeys touch down, then milliseconds after that, the front tires of the inner and outer bogeys touch at the same time. then of course the nose gear. as I said, it works this way, to minimize shock transfer and rebound to the airframe. ever watched some of the bouncy landing attempts of a 737?................shock transference to the airframe working at its best.
Right on the Money Rich!
747 Jumbo Jet - watch those wheels touch down (1 min 57 sec)
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Old Nov 27, 2012, 04:35 PM
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So I was just about to pick up 64mm edf units from HK when I came across these new change sun 12 blade 70mm guys. http://www.windrider.com.hk/product.asp?id=170

The blade is 68 mm so it would work with the size of my nacelles and might be pretty cool looking/sounding. Any thoughts?
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Old Nov 27, 2012, 05:24 PM
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So I was just about to pick up 64mm edf units from HK when I came across these new change sun 12 blade 70mm guys. http://www.windrider.com.hk/product.asp?id=170

The blade is 68 mm so it would work with the size of my nacelles and might be pretty cool looking/sounding. Any thoughts?
I bought 6 of these CS fan units myself. .. . Fairly well balanced I have yet to power them up yet. . . .they are on my 767-200.
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Old Nov 28, 2012, 02:25 AM
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The changesun 70mms are the best I've ever used in my edf jets.
Sound is georgeous and power is ok.
I have them in my A319 and my new G-V will them also have.
Best choice.
Markus
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Old Nov 28, 2012, 06:23 PM
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The changesun 70mms are the best I've ever used in my edf jets.
Sound is georgeous and power is ok.
I have them in my A319 and my new G-V will them also have.
Best choice.
Markus


I appreciate the comments. I went ahead and ordered 4 of them. The next big question is battery and motor combo. I am planning the turnigy 2855 in 2800kv with 4 4s 2200 30-40c batteries. I would like a little larger batteries but am worried weight will be an issue. I figure that once its in the air a lot of circling will be next without insane power usage. Not sure what flight times will be with that set up.
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Old Nov 28, 2012, 07:26 PM
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I appreciate the comments. I went ahead and ordered 4 of them. The next big question is battery and motor combo. I am planning the turnigy 2855 in 2800kv with 4 4s 2200 30-40c batteries. I would like a little larger batteries but am worried weight will be an issue. I figure that once its in the air a lot of circling will be next without insane power usage. Not sure what flight times will be with that set up.
Sounds Good, those motors will be great! Rlebaron do you have the link to these motors?
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Old Nov 28, 2012, 08:40 PM
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Sounds Good, those motors will be great! Rlebaron do you have the link to these motors?
Here's the link.

http://www.hobbyking.com/hobbyking/s...ner_630w_.html

I figure with a 60 amp esc it should be fine.

The nacelles are going to have to be cut and carved from pretty dense foam as I think the overall width to keep it scale is 84mm, giving me a nacelle shell about 6-7 mm thick- no problem right?
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Old Nov 28, 2012, 09:13 PM
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Another question for you all. My planned weight is somewhere in the 7-8 lb range, wingspan is 62". I am ordering servos and was going to go with the 13g metal gear Turnigy 9018MG guys for the ailerons, elevators and nose steering servos. The remainder-flaps, spoilers and rudder will be simple 9g servos. Opinions- too small, just right, MG overkill?
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Old Nov 29, 2012, 12:12 AM
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Cathay Pacific Cargo 747-8 just flew over my house at about 5000 feet, heading for Toronto airport. what a sound coming from those Trents. very low rumble of moving air. absolutely incredible.
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Old Nov 29, 2012, 08:50 PM
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Cathay Pacific Cargo 787-8 just flew over my house at about 5000 feet, heading for Toronto airport. what a sound coming from those Trents. very low rumble of moving air. absolutely incredible.
I've never seen one in person- can't wait to though. Not many heavies make it to Albuquerque.

Just saw these- don't know how I missed them before- some amazing design and build skills.

RC 747 - Air Design Modelismo - Maiden Flight (7 min 36 sec)


RC 747 - Air Design Modelismo - Flight 3 (6 min 20 sec)


Also, one question for those chiming in- I increased the size of the elevator by about 15-20%. To me it still looks like I'll need something bigger- Thoughts? I guess it will work but would hate to finish it all and realize it needed a little more.
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Old Nov 29, 2012, 09:19 PM
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the elevator will be fine. I wouldn't increase it anymore than you have.
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Old Nov 29, 2012, 09:22 PM
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the elevator will be fine. I wouldn't increase it anymore than you have.
Sounds good. Thanks.
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